The effectiveness of brief intervention in diverse populations and across the spectrum of alcohol problems is not clear. In hospitalized patients, there is a unique opportunity for identification of and brief intervention for alcohol problems: the prevalence of problems is high, patients who otherwise might not seek care are accessible, and alcohol-related medical illness can improve patients' receptiveness to interventions. The objective of this project, Addressing the Spectrum of Alcohol Problems (Project ASAP), is to test whether screening and brief intervention for hazardous, harmful, and dependent drinking leads to improved alcohol-related outcomes and is cost-effective. We will screen medical inpatients at Boston Medical Center with the Alcohol Use Disorders Identification Test to identify a cohort of 500 subjects with alcohol problems. The cohort will be randomized into two groups and followed for one year. Subjects in one group will receive standard care; each individual in the other group will receive a brief intervention tailored to the severity of his or her alcohol problem. All patients will be assessed at baseline regarding alcohol diagnosis, consumption and problems, readiness to change, health-related quality of life, and medical and alcohol treatment utilization. Subjects will be interviewed at three and twelve months after enrollment. Primary outcomes are alcohol consumption and linkage to alcohol treatment. Additional outcomes include health-related quality of life, health care utilization, alcohol problems, and readiness to change. Costs, and clinical outcomes measured in quality-adjusted life years, a standard metric that allows comparison to other chronic illnesses, will be compared in a cost- effectiveness analysis. The analysis will be the basis for the development of a comprehensive simulation model, the Alcohol Intervention Policy Model (AIM). This AIM will provide a framework for the understanding of the policy implications of a range of alcohol treatment effectiveness studies. The hypothesis to be tested is that relative to standard care, a strategy of screening and brief intervention for medical inpatients with alcohol problems is highly cost-effective compared to other accepted health care interventions. By enrolling a diverse group of patients, conclusions of this study will be broadly generalizable. If the intervention is effective, these findings could lead to broader implementation of brief intervention for alcohol problems in an accessible high-risk population, hospitalized patients.